Cleavage and implantation Day 1 ===== Day 14 陳建榮 http://web.nchu.edu.tw/pweb/users/chenjr/

Cleavage in mammalian zygote

Morula 桑椹胚

桑椹胚 內細胞團或胚球層 囊胚腔 囊胚 滋養層

卵裂型態(cleavage patterns): 完全分裂(total or holoblastic cleavage): 哺乳類動物(有胎盤哺乳類)之無(或寡)卵黃卵屬之 部份分裂(partial or meroblastic cleavage): 鳥類之端卵黃卵屬之。

Mature Xenopus oocyte

完全分裂(total or holoblastic cleavage): Spiral cleavage Radial cleavage

部份分裂(partial or meroblastic cleavage): Incomplete cleavage Superficial cleavage

Cleavage in Zebra Fish

Monozygotic twin同卵雙生

Estrogen抑制受精卵向子宮移動 Progesterone加速受精卵向子宮移動

Morula stage 犬: 10-11days 家畜: 5-9 days

Implantation types著床型態: 依滋養層與子宮內膜之間接觸的程度，及子宮內膜的被破壞情形可分為 1.間質性著床(interstitial implantation) -靈長類，囓齒類，及部分肉食動物，其胚埋入子宮內膜發育，一直到出生 2.築巢性著床(nidation implantation)或表面著床(superficial implantation): -大多數的家畜，滋養細胞並不會破壞子宮內膜。

築巢性著床 (nidation) 間質性著床 (interstitial) carnivores, ruminants, horses, and pigs rats and mice humans, and guinea pigs

Interstitial implantation間質性著床: 步驟： Invade侵入 Ingestive吞食 Digestive消化 E6 ~ E11 Trophoblast 滋養層 Syncytiotrophoblast Cytotrophoblast -Inner cell mass (embryoblast)胚球層  bilaminar embryonic disc雙層胚盤

Trophoblast滋養層 : Cytotrophoblast細胞滋養層 Syncytiotrophoblast合體滋養層 EPF (early pregnancy factor)早期妊娠因子 24～48hr -- 10 days In mothernal serum hCG人類絨毛性腺激素 10 days In mother’s urine Embryoblast (inner cell mass) Hypoblast下胚層 (primary endoderm) hCG  corpus luteum  progesterone 妊娠試驗： hCG、EPF Inhibition of implantation Diethylstilbestrol”事後丸” RU486”流產藥丸”

築巢性(nidation)或表面著床(superficial implantation) 進行方式: -並置(apposition):囊胚平均排列於子宮或子宮角腔內、雙子宮的動物如兔子則無此現象。 -黏接(adhension):囊胚與子宮內膜接觸，子宮內膜上皮與滋養細胞連接甚緊。 -附著(attachment):有蹄類的滋養細胞與子宮黏膜上皮之間形成微絨毛性指間構造。

著床開始的時期與完成的時間因動物而異 ─ ─ ──┬────────────────────── ──── ──── 動物 │開始 並置 接觸 附著 完成 ── ─ ─┼────────────────────── ──── ──── 貓 │11-12 16-17 (5) 狗 │14-17 20-21 (4-6) 牛 │ 8-32 40-45 (13-32) 綿羊 │4-16 10 16 28-35 (19-24) 馬 │5-40 38-39 95-105 (65-90) 豬 │2-13 12 13-14 16-18 24-26 (13-22) 人 │6-7 12-13 (6) ────────────────────────── ──── ──── ──── *時間是以授精後算起。

人工受孕 男性不孕 數目太少 品質太差 無精子 女性不孕 輸卵管阻塞 子宮切除 自發性流產 Intracytoplasmic sperm injection Surrogate mothers

Intracytoplasmic sperm injection

子宮外孕(ectopic pregnancies) Human Placenta previa前置胎盤 家畜：Antimesometrial 對子宮系膜

Day 8 Inner cell mass Bilaminar disc雙層胚盤 Hypoblast下胚層 Epiblast上胚層  Amnion羊膜 +Epiblast上胚層 Amnoitic cavity羊膜腔  Hypoblast下胚層 exocoelomic membrane外胚腔膜 Blastocytic cavity囊胚腔  Exocoelomic cavity外胚腔腔室 (primary yolk sac初級卵黃囊)

Day 9 Extraembryonic mesoderm胚外中胚層 Syncytiotrophoblast Lacuna陷窩

Day 10 - 12 Lacunar  lacunar network Syncytiotrophoblast ↓ Endomatrial stromal cell  Decidual cell蛻膜細胞 => decidual reaction蛻膜反應 Extraembryonic mesoderm胚外中胚層 Extraembryonic coelomic space胚外體空隙

Closing plug閉鎖栓

Decidual cell蛻膜細胞

Day 13 Extraembryonic mesoderm胚外中胚層 Extraembryonic coelomic space胚外體空隙 Extraembryonic somatic mesoderm胚外壁層中胚層 Extraembryonic splanchnic mesoderm胚外臟層中胚層 Chorion絨毛膜 Extraembryonic somatic mesoderm Cytotrophoblast Syncytiotrophoblast Extraembryonic coelom胚外體腔 Chorionic cavity絨毛膜腔

Day 14 Primary yolk sac Secondary yolk sac Remnant of primary yolk sac Cytotrophoblast  Primary chorionic villus初級絨毛膜絨毛 Hypoblast  Prechordal plate脊索前板